News|Articles|July 4, 2026

10 Infectious Disease Developments That Defined Q2 2026

The second quarter of 2026 delivered a remarkable concentration of regulatory milestones, outbreak events, and pipeline advances across infectious disease. From the first-ever US approval for hepatitis delta virus to landmark HIV treatment options and a cruise ship outbreak that put the country's biopreparedness infrastructure to the test, the April–June period was among the most consequential quarters for the field in recent memory. The Contagion team covered each development as it unfolded. Here is a summary of 10 of the most significant stories from Q2 2026.

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UTI guidelines are moving away from complicated or uncomplicated infections to localized or systemic classification terminologies. Guidelines author Zachary Nelson, PharmD, MPH, BCIDP, provides further insights on the changes including applying antibiograms, potential costs, and whether clinicians will embrace these new classifications.

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IDSA/ESCMID panel member Henry Chambers, MD, explains why the new S aureus bacteremia guidance replaces the complicated vs uncomplicated label with risk stratification, and how the statements are akin to the stages of cancer in guiding treatment decisions associated with this bacteremia.

October 1st, 2026

Further Insights, Treatment Considerations Around the PETERPEN Study

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September 29th, 2026

VYD2311 Shows Superior Tolerability to mRNA COVID-19 Vaccine in Phase 3 Study

In the phase 3 LIBERTY study, the investigational monoclonal antibody, VYD2311, had significantly fewer adverse events than an mRNA COVID-19 vaccine, and it did not blunt vaccine-induced neutralizing titers when the two were given together.

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September 26th, 2026

Environmental Stewardship: The Role of Antimicrobials in Climate Change

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